Beavers, known for their dam-building activities, possess a diet heavily reliant on woody plant material. This dietary selection is not for direct nutritional gain from the wood itself, but rather for accessing the cambium layer, a thin region of actively dividing cells located just beneath the bark of trees. This layer is significantly richer in nutrients, including sugars and proteins, than the bulk of the wood.
The consumption of trees and shrubs serves multiple critical purposes for these industrious rodents. The cambium provides sustenance, while the structural components of the trees, specifically the wood, are used in the construction of dams and lodges. These structures are essential for creating wetland habitats that offer protection from predators and access to food resources, especially during winter months. Historically, this reliance on woody resources has shaped ecosystems, influencing forest composition and water flow in numerous regions.